U.S. patent application number 12/486955 was filed with the patent office on 2010-12-23 for image alignment procedure.
This patent application is currently assigned to XEROX CORPORATION. Invention is credited to JACK ELLIOT, ABU SAEED ISLAM, RAKESH SURESH KULKARNI.
Application Number | 20100322688 12/486955 |
Document ID | / |
Family ID | 43354525 |
Filed Date | 2010-12-23 |
United States Patent
Application |
20100322688 |
Kind Code |
A1 |
ISLAM; ABU SAEED ; et
al. |
December 23, 2010 |
IMAGE ALIGNMENT PROCEDURE
Abstract
This is an alignment system where precise alignment of a
reproducible image is obtained with respect to the paper. An imaged
paper to be reproduced is placed on a light table having a right
angle fitting or marking. The paper is placed on top of the light
table and is aligned with this right angle marking. A transparent
platen with marked scales is placed over the imaged paper and also
aligned with the right angle fitting. The scales are placed over
the corners of the image and image corner location readings are
taken from the scales. These readings are then entered and fixed
into a marking system such as an electrophotographic printer for
reproduction of copies from the aligned and fixed original
image.
Inventors: |
ISLAM; ABU SAEED;
(ROCHESTER, NY) ; KULKARNI; RAKESH SURESH;
(WEBSTER, NY) ; ELLIOT; JACK; (PENFIELD,
NY) |
Correspondence
Address: |
XEROX CORPORATION;Attn: Law Offices of James J. Ralabate
Patent Documentation Center, 100 Clinton Ave South, MS: XRX2-020
Rochester
NY
14644
US
|
Assignee: |
XEROX CORPORATION
NORWALK
CT
|
Family ID: |
43354525 |
Appl. No.: |
12/486955 |
Filed: |
June 18, 2009 |
Current U.S.
Class: |
399/379 |
Current CPC
Class: |
H04N 1/10 20130101; H04N
2201/0422 20130101; G03G 15/607 20130101; H04N 1/1061 20130101 |
Class at
Publication: |
399/379 |
International
Class: |
G03G 15/00 20060101
G03G015/00 |
Claims
1. A paper reproducible image alignment assembly comprising: a
light table with a right angle fitting on a table top portion, and
a transparent platen with at least three marked scales positioned
in corners of said platen, said right angle fitting positioned in
at least one corner section of said light table and configured to
receive and align an aligned paper sheet placed at its right angle
location, said light table having a light transparency portion at
said table top portion, said transparent platen configured to be
positioned above said aligned paper sheet where said marked scales
are readably positioned above at least three corners of an image on
said aligned paper sheet.
2. The assembly of claim 1 wherein said right angle fitting is
raised above a surface of said table top portion.
3. The assembly of claim 1 wherein said marked scales have
graph-like horizontal and vertical intersecting lines that are
configured to indicate and mark a location of an image below said
scales.
4. The assembly of claim 1 wherein said platen is made from
transparent glass having etched said scales thereon.
5. The assembly of claim 1 wherein there are from 3 to 6 scales,
each of said scales having numerical designations for each
horizontal and vertical intersecting lines positioned thereon so
that said numerical designations can be recorded and entered into
an image marking apparatus.
6. The assembly of claim 1 wherein said platen is made from a
member selected from the groups consisting of transparent glass,
transparent films, transparent plastics, transparent compositions
and mixtures thereof.
7. The assembly of claim 1 wherein said marked scales are selected
from the group consisting of etched scales, photo-plotted scales,
permanent ink scales and mixtures thereof.
8. The assembly of claim 1 wherein said scale is configured to
receive cross hairs designating a location of an image corner, said
cross hairs being located at marked and readable positions on
horizontal and vertical lines located on said scale.
9. A process for aligning a reproducible image on a media or paper
sheet, said process comprising: providing a light table with a
right angle fitting on a transparent table top portion, providing a
transparent platen with at least three marked scales positioned in
corners of said platen, aligning an imaged paper with said right
angle, fitting on said table top portion, placing said transparent
platen on said paper with said scales in areas where images or
marks on said paper are to be measured, aligning said platen to a
same right angle used to align said imaged paper on said right
angle fitting, reading(s) off locations of said marks as indicated
by cross hairs on said scales, and entering said readings into a
marking apparatus for fixing said readings for reproductions of
said images or markings.
10. The process of claim 9 wherein said readings are recorded and
placed on a table prior to entering said readings into said marking
apparatus.
11. The process of claim 9 wherein there are from 3-6 said marked
scales, each having graph-like horizontal and vertical intersecting
lines, said lines configured to indicate a location of said images
or markings on said paper sheet.
12. The process of claim 9 wherein said platen is constructed of a
transparent material having etched or photo-plotted said
scales.
13. The process of claim 9 wherein said marking apparatus is an
electrophotographic marking machine.
14. The process of claim 9 wherein said right angle fitting is
raised above said table top portion.
15. The process of claim 9 wherein different measurements between
said images are designated as parameters a, b, c, d, e, f, g, and
h, and said measurements are recorded on a table and subsequently
entered into said marking apparatus.
16. The process of claim 9 wherein images on both sides of said
paper sheet are aligned and recorded in said marking apparatus.
Description
[0001] This invention relates to image alignment assemblies and
processes of any marking systems.
BACKGROUND
[0002] The alignment assembly and process of this invention is
appropriate for use in aligning any reproducible image in any
marking system. However, for the sake of clarity, the present
invention will be described herein as it relates to
electrophotographic marking systems.
[0003] In electrostatographic process, a system is used whereby a
uniform electrostatic charge is placed upon a reusable
photoconductive surface. The charged photoconductive surface is
then exposed to a light image of a scanned original document to
selectively dissipate the charge to form a latent electrostatic
image of this original on the photoreceptor. The latent image is
developed by depositing finely divided marking and charged
particles (toner) upon the photoreceptor surface. The charged toner
is electrostatically attached to the latent electrostatic image
areas to create a visible replica of the original. The toned
developed image is then transferred from the photoconductor surface
to a final image support material, such as paper, and the toner
image is fixed thereto by heat and pressure to form a permanent
copy corresponding to the original.
[0004] In xerographic systems of this type, a photoreceptor surface
is generally arranged to move in an endless path through the
various processing stations of the xerographic process. The
photoconductive or photoreceptor surface is generally reusable
whereby the toner image is transferred to the final support
material and the surface of the photoreceptor is prepared to be
used once again for another reproduction of an original scanned
document.
[0005] Several methods are known for applying an electrostatic
charge to the photosensitive member such as the use of
electron-emitting pins, an electron-emitting grid, single
corona-charging structures and single for multiple dicorotron wire
assemblies. In recent development of high speed xerographic
reproduction machines where copiers can produce at a rate of or in
excess of three thousand copies per hour, the need for reliable and
properly aligned reproducible and final copies is required.
[0006] Image on paper errors can show up as absolute position
errors, magnification or shrinkage errors and image skew errors.
Position errors are caused by the paper alignment devices.
Magnification and shrinkage errors are caused due to shrinkage of
paper in the fuser and errors in photoreceptors or ROS polygon
speeds. Skew errors are caused by ROS skew and errors in image
alignment devices. In the alternative current procedures for image
on paper registration on electrostatic printing machines is
extremely tedious, iterative and cumbersome. It involves printing
internal test prints and manual measurement of different artifacts
on every side of the paper with a flexible scale and inputting
those values to the printer. This is done in a serial fashion, one
factor at a time, resulting in a long setup time and setup errors
and customer dissatisfaction.
SUMMARY
[0007] The various embodiments of the present invention provide a
system, process and apparatus whereby precise and proper alignment
of an image on an original to be reproduced document is effectively
achieved.
[0008] This invention proposes an alternate way of measuring
location of marks on paper for registration setup. The procedure
(and alignment assembly) consists of aligning the paper to be
measured on a light table with right angle edges. A glass (or other
suitable material) platen with etched scales in the areas where the
marks are to be measured will be then placed on the paper aligning
it to the same right angle edges. The locations of the marks will
then be read off the scales on the glass platen using an eye loupe,
if the image needs magnification.
[0009] There is currently provided in most xerographic marking
machines a menu that accepts input on several aspects of the
machine. One of these is "image registration" input where the user
enters prior image measurements of the different artifacts or
features in order to set and fix these measurements in the marking
machine. Generally, in the prior art, a reference table is provided
where the various measurements are entered in the table. For
example, a measurement "a" which may be a diagonal measurement is
taken from an upper left corner of the image to a lower right
corner of the image. Other separate measurements b, c, d, e, f and
g are also taken and indicated in the table before the completed
table is entered into the machine. This prior art procedure is very
time consuming (about 35 minutes for each image) and tedious.
[0010] In the present invention, a procedure and assembly is
provided for image alignment that can be completed in 5-10 minutes,
is much less tedious and accomplishes, for the user a very accurate
image alignment. A recording table is used in the prior art and in
the present invention. However, the measurements obtained for
entrance in the table are significantly reduced in the present
invention, as above noted.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 illustrates a prior art alignment procedure which
indicates the various measurements that are required.
[0012] FIG. 2 illustrates the light table with raised right angle
edges for use in paper alignment and the paper aligned thereon.
[0013] FIG. 3 shows the platen with the scales to be placed over
the imaged paper.
[0014] FIG. 4 illustrates the glass platen with etched scales as it
is placed over the paper and used in measuring the image
distances.
[0015] FIG. 5 illustrates the etched scale(s) used in an embodiment
of the present invention with reference numbers.
[0016] FIG. 6 illustrates a typical table used to enter the
measurements in the marking machine.
DISCUSSION OF DRAWINGS AND PREFERRED EMBODIMENTS
[0017] In FIG. 1, a prior art imaged (image not shown for clarity)
sheet 1 is illustrated having various measurements indicated
thereon. The corners 2, 3, 4, and 5 of the images are measured "b"
measurement being the diagonal measurement from the upper left
corner 2 of the image to the lower right corner 5 of the image. "c"
is the measurement taken by the user from the upper left corner 2
of the image to the upper right corner 3 of the image. "d" is the
measurement from the upper right corner 3 of the image to the lower
right corner 5 of the image. "e" is the measurement of the distance
from the upper right corner 3 of the image to the right edge 6 of
the paper 1. "f" is the measurement of the lower right corner 5 of
the image to the right edge 6 of the paper 1. "g" is the
measurement of the distance between the upper right corner 3 of the
image to the top edge 7 of the paper 1. "f" is the measurement of
the distance between the lower right corner 5 of the image to the
bottom edge 8 of paper 1. Each measurement b, c, d, e, and f is
tediously measured by a ruler, yardstick or any other manual device
until all are recorded, then entered into a table (see FIG. 6) for
entrance into the marking machine. This prior art process consumes
about 35 minutes for each imaged side of paper 1.
[0018] FIG. 2, a light table 9 used in an embodiment of the present
invention is illustrated having a right angle edge 10 (which may
preferably be raised) for receiving an imaged paper 1 and alignment
of the upper or top right paper edge 7 within the right angle edge
10 on light table 9. Once the paper 1 is aligned within the right
angle edge 10, the glass (or other material) platen 11 with etched
scales 12 of FIG. 3 is placed over the imaged paper 1 as shown in
FIG. 4 with each scale 12 placed over the corners 13 of the image.
The locations of the marks 13 will then be read off the scales 12
on the glass platen 11 using an eye loupe. The "light table" used
in the present invention is defined as a table with a light
transmitting top portion that is configured to make visible an
image on the paper side opposite the imaged side. The right angle
fitting can be etched on the table top, marked on the table top, or
a raised right angle portion like an inverted L shape. The light
from the light table must be strong enough to provide visibility of
the image through to the scales used to measure the locations of
the image. An eye loupe can be used to read the scales on the
platen if the scales are too small to read without
magnification.
[0019] FIG. 5 illustrates the scale(s) 12 in a blown up view having
marked vertical 14 and horizontal 15 measurement lines. These lines
in one embodiment are marked from 1-10. The image corner marks 13
can be viewed through the transparent platen 11 and easily read.
After the location of the cross hairs or marks 13 are measured with
the etched scale 12 (in FIG. 5, lines 18 meet at 4 and 6), the
parameters b, c, d, e, f, g and h could be easily determined and
typed as actual measurement 17 in the table 16 (of FIG. 6) for
registration setup and entrance into the xerographic copier or
printer.
[0020] This is an alignment system where precise alignment of a
reproducible image with respect to paper is obtained. An imaged
paper to be reproduced is placed on a light table having a right
angle fitting or marking. The paper is placed on top of the light
table and is aligned with this right angle marking. A transparent
platen with marked scales is placed over the imaged paper and also
aligned with the right angle fitting. The scales are placed over
the corners of the image and image corner location readings are
taken from the scales. These readings are then entered and fixed
into a marking system such that the printer can make the necessary
corrections for accurate alignment of the image with respect to the
paper.
[0021] The location of the cross hairs on side 2 could be measured
by flipping the test target or the light table could enable the
measurements of both sides simultaneously. In another embodiment,
it could be conceived that the glass platen with the scale hinged
in on the light table with the edges for ease of use. Alternately,
to reduce cost, a strong polyester film with photo-plotted scales
can be used in place of the glass platen.
[0022] The readings on the table of FIG. 6 are entered from the
table into the menu portion of the marking machine for a permanent
fix for reproduction of the aligned image, for example, in
reproducing a page of a book for 100 or so reproductions.
[0023] The embodiments of the present invention provide a paper
reproducible image alignment assembly comprising a light table with
a right angle fitting on a table top portion and a transparent
platen with at least three marked scales positioned in corners of
the platen. This right angle fitting is positioned in at least one
corner section of the light table and is configured to receive and
align an aligned paper sheet placed on top of the table at its
right angle location.
[0024] The light table has a light transparency portion at the
table top portion. The transparent platen is configured to be
positioned above the aligned paper sheet where the marked scales
are readably positioned above at least three corners of an image on
the aligned paper sheet. In one embodiment, the right angle fitting
is raised above a surface of the table top portion.
[0025] The marked scales have graph-like horizontal and vertical
intersecting lines that are configured to indicate and mark a
location of an image below the scales. In one embodiment, the
platen is made from transparent glass having etched scales thereon.
Generally, there are from 3 to 6 scales. Each of the scales have
numerical designations for each horizontal and vertical
intersecting lines positioned thereon so that numerical
designations read can be subsequently recorded and entered into an
image-marking apparatus.
[0026] In another embodiment, the platen is made from a member
selected from the groups consisting of transparent glass,
transparent films, transparent plastics, transparent compositions
and mixtures thereof. The marked scales are selected from the group
consisting of etched scales, photo-plotted scales, permanent ink
scales and mixtures thereof. The scale is configured to receive
cross hairs designating a location of an image corner. These cross
hairs are located at marked and readable positions on horizontal
and vertical lines located on the scale.
[0027] The process of using this above assembly comprises providing
a light table with a right angle fitting on a transparent table top
portion, providing a transparent platen with at least three marked
scales positioned in corners of the platen, aligning an originally
to be reproduced imaged paper with the right angle, fitting on the
table top portion, placing the transparent platen on the paper with
the scales placed above areas where images or marks on the paper
are to be measured, aligning the platen to a same right angle used
to align the imaged paper on the right angle fitting, reading(s) of
locations of the marks as indicated by cross hairs on the scales
and entering these readings into a marking apparatus for fixing
these readings for reproductions of original images or
markings.
[0028] In this process, the readings are recorded and placed on a
table prior to entering the readings into the marking apparatus.
Generally, there are from 3-6 marked scales, each having graph-like
horizontal and vertical intersecting lines. These lines are
configured to indicate a location of the images or markings on the
paper sheet.
[0029] The platen is constructed of a transparent material having
etched or photo-plotted scales. In one embodiment, the marking
apparatus is an electrophotographic marking machine. The right
angle fitting is preferably raised above the table top portion.
[0030] The different measurements taken between the images are
designated as parameters a, b, c, d, e, f, g and h and these
measurements are recorded on a table and subsequently entered into
and fixed in the marking apparatus for reproduction of aligned
images on the reproduced papers. This invention provides that
images on both sides of the paper sheet are aligned and recorded in
the marking apparatus.
[0031] It will be appreciated that variations of the
above-disclosed and other features and functions, or alternatives
thereof, may be desirably combined into many other different
systems or applications. Various presently unforeseen or
unanticipated alternatives, modifications, variations, or
improvements therein may be subsequently made by those skilled in
the art which are also intended to be encompassed by the following
claims.
* * * * *